Hi, hello once again, its very interesting as i also keep going back to this area (Loughgilly) and keeping an open mind in regards the name spelling, your right with the literacy at the time and also of interest my Robert Kearns Born about 1830 named his children Elizabeth, Margaret, Jane, Robert, and also a Joseph and there was two others that died very young called John and Mary.
I dont know if my Robert had any siblings but do suspect that he might have had a sister called mary, but this is not proven yet, Roberts father was named John Kearns as per Roberts Marriage.
My Joseph ended his days in Toronto Canada, i dont know why he left the UK for Canada but he did have a second marriage when living there.